x_max = 2*pi;
N = 128;
k = 1e-3;
T = pi;
max_iter = round(T/k);

init_u = initial_data1(N,x_max);
u1 = leapfrog_highorder(init_u,N,x_max,k,2,max_iter);
u2 = leapfrog_highorder(init_u,N,x_max,k,4,max_iter);
u3 = leapfrog_highorder(init_u,N,x_max,k,6,max_iter);

plot_fig(x_max,N,u1,u2,u3);
